feat: add readable duplex messaging

Assistant: codex
Assistant-Model: gpt-5.6-sol
Assistant-Session: 01a03397-4d51-7fd1-8ff2-946eb22ea2bc

tests/test_line_limits.py

@@ -0,0 +1,65 @@
+from concurrent.futures import ThreadPoolExecutor
+
+from tamq.broker import BrokerIdentity, InputBroker
+from tamq.store import Store
+
+
+def test_window_counters_survive_reopen_and_isolate_repositories(tmp_path, monkeypatch):
+    monkeypatch.setattr("tamq.broker.validate_targets", lambda targets: None)
+    path = tmp_path / "queue.sqlite3"
+    store = Store(path)
+    left = InputBroker(store, BrokerIdentity("session-1", "left"), limits=(1, 10, 10))
+    right = InputBroker(store, BrokerIdentity("session-1", "right"), limits=(1, 10, 10))
+    assert left.inspect_operator_line("To:target: left") is not None
+    assert right.inspect_operator_line("To:target: right") is not None
+    store.close()
+
+    reopened = Store(path)
+    assert reopened.line_state("session-1", "left")["messages"] == 1
+    assert reopened.line_state("session-1", "right")["messages"] == 1
+    blocked = []
+    left = InputBroker(
+        reopened,
+        BrokerIdentity("session-1", "left"),
+        limits=(1, 10, 10),
+        notify=blocked.append,
+    )
+    assert left.inspect_worker_line("To:target: blocked") is None
+    assert "lines of messages" in blocked[-1]
+
+
+def test_atomic_message_admission_does_not_cross_limit(tmp_path, monkeypatch):
+    monkeypatch.setattr("tamq.broker.validate_targets", lambda targets: None)
+    path = tmp_path / "queue.sqlite3"
+    seed = Store(path)
+    seed.configure_window("session-1", "source", (1, 100, 100))
+    seed.close()
+
+    def send(body):
+        store = Store(path)
+        try:
+            broker = InputBroker(
+                store,
+                BrokerIdentity("session-1", "source"),
+                limits=(1, 100, 100),
+            )
+            return broker.inspect_worker_line(f"To:target: {body}") is not None
+        finally:
+            store.close()
+
+    with ThreadPoolExecutor(max_workers=2) as executor:
+        accepted = list(executor.map(send, ("one", "two")))
+    assert sorted(accepted) == [False, True]
+    final = Store(path)
+    assert len(final.list()) == 1
+    assert final.line_state("session-1", "source")["messages"] == 1
+
+
+def test_new_session_generation_starts_a_fresh_ledger(tmp_path, monkeypatch):
+    monkeypatch.setattr("tamq.broker.validate_targets", lambda targets: None)
+    store = Store(tmp_path / "queue.sqlite3")
+    first = InputBroker(store, BrokerIdentity("generation-1", "source"), limits=(1, 10, 10))
+    second = InputBroker(store, BrokerIdentity("generation-2", "source"), limits=(1, 10, 10))
+    assert first.inspect_operator_line("To:target: first") is not None
+    assert second.inspect_operator_line("To:target: second") is not None
+    assert len(store.list()) == 2